Pieces of furniture which include at least one internal storage space are often equipped with doors or leaves that open and close by rotating around a horizontal or vertical axis using a hinge mechanism. A very common system, which is widely used in the furniture industry, is provided with hinges for supporting the doors in the closed position that are hidden when the door of the piece of furniture is closed.
U.S. Pat. Nos.3,362,042 and 4,226,001, for example, describe these types of hinges in detail. The hinges described in these documents have several advantages that have determined their popularity and widespread use on the market. The described alternative versions use different types of springs in the hinge to produce a biasing force when the door to which they are attached is closed. Consequently, the doors on the piece of furniture close in a facilitated and very precise manner. Unfortunately, in these cases it is almost always necessary to exert an additional external force to open the door of the piece of furniture, which entails the availability of some type of handle. Sometimes, doors with handles or other outwardly visible gripping devices are not desirable. Therefore, a device with a spring that generates an opening moment on the door must be used to open the door. To accomplish this, the spring must be separate from the hinges, or highly complex hinges are required.